Self-adjusting mill-roll supporting mandrel



Sept. 26, 1961 R. H. SCHUL-rz ETAL 3,001,736

SELF-ADJUSTING MILL-ROLL SUPPORTING MANDREL Filed Feb. 8, 195e s sheets-sheet 1 Sept. Z6, 1961 R. H. scHUL-rz Erm. 3,001,736

SELF-ADJUSTING MILL-ROLL SUPPORTING MANDREL 5 Sheets-Sheet 2 Filed Feb. 8, 1956 &a

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Sept. 26, 1961 R. H. scHULTz ETAL 3,001,736

SELF-ADJUSTING MILL-ROLL SUPPORTING MANDREL.

Filed Feb. 8, 1956 5 Sheets-Sheet 3 MSW mit Sie@ ,Page OT j 3,991,736 j SELF-ADEUSTING Msli-ROLL SUPPORTING MANEBREL Rudolph H. Schultz, 225 Highland Blvd., Brooklyn, NSY.,

and Adam .lames Siebert, 171-01 Courtneyl Ave.,

Flushing, NX.; Bertha E. Siebert, executrix of said Adam James Siebert, deceased Filed Feb. 8, 1956, Ser. No. 564,255 8 Claims. (Cl. 242-72) The present invention relates to a self-centering mandrel for simultaneously supportingY and gripping the core of a relatively large mill-roll of web material while the web is being fed to any desired type of machine by which the web of material lis being processed.

A principal object of the invention'is to provide a sell adjusting supporting mandrel which will positively engage the internal surface of the hollow core of. a large mill-roll of web material for applying a continuous control torque to the mill-roll as the web Iis unwound.' Ordinarily, the control torque will be unidirectional and will be provided by a controllable brake for. regulating the tension in the web.

The usual types of mandrel for this purpose -involve axially movable conical members or may utilize hollow shafts which may be expanded to engage the hollow core of lthe mill-roll by various mechanisms such as precision wedges, pneumatically actuated means, and may include manually operable means for quickly engaging or releasing the core ofthe mill-roll;

One of the objects'of the present invention is to'provide a self-adjusting supporting mandrel which centers the mill-roll coaxially with the mandrel and which increases its gripping action with respect to the mill-roll in accordance with increasing torque transmitted between the mandrel and the mill-roll core.

Another object of the invention is to provide a mandrel of this character which maybe adjusted laterally to receive mill-rolls having the sameinternal core diameter but wound with webs of diierent widths.

A further object of the invention is to provide a mandrel of this character which is rugged, inexpensive to manufacture, and which has no projecting moving parts which could accidentally cause personal injuries tov operating or maintenance personnel.

Generally, the invention comprises a main shaft arranged to be mounted in and controlled by the processing machine to which the web is delivered from the mill-roll. The shaft of the mandrel is provided with spaced supporting collars over which the core of the mill-rollmay slide freely. Disposed intermediate the supporting collars of the mandrel are a plurality of gripping aps which are symmetrically and uniformly angularly spaced with respect to the rotational axis of the mandrel and which are individually pivoted each tor limited angular movement about an axis parallel to the rotational axis of the mandrel. The free edges of' the gripping ilapsV engage the internal surface of the mill-roll core, spring means being provided lto press them yieldiugly into engagement with cylindrical core surface. The pivotal axes of the gripping ilaps are so positioned 'that relative rotation between the mill-roll core and the mandrel in one direction will urge the outer edges of the gripping aps outwardly and cause them to dig into locking engagement with the core. Relative rotation in the opposite direction will urge the flaps inwardly against the yielding pressure of the spring mechanism to unlock the gripping aps and release the mandrel for removal from an emptymill-roll core. Cam surfaces are provided at one end of the gripping flaps to press the diaps inwardly when the mandrel is inserted in a mill-roll core.

Other objects, featuresA and advantages of the' invention will become apparent upon reading the following 2 specitication together with the accompanying drawing forming a part hereof.

Referring to the drawing:

FIGURE 1 is a perspective view of a mandrel in accordance with the invention, the mill-roll being shown in dotted outline.

FIGURE 2 is a transverse sectional view taken along the line 2 2 of FIG. l, looking 4in the direction of the arrows.

FIGURE 3 is a longitudinal sectional view, partly broken away to illustrate details of construction, the view being taken generally along the line 3--3 ot FIG. 1.

FGURE 4 is a transverse sectional view taken along the line 4--4 of FIG. 3.

FIGURE 5 is a transverse sectional view taken along the lline 5--5 of FIG. 3 with the mill-roll removed.

FIGURE 6 is a fragmentary view similar to FIG. 5 showing one of the gripping ilaps in engagement with the mill-roll core.

FIGURE 7 is a plan fragmentary sectional view taken along the line 7-7 of FIG. 4.

v FEGURES 8a and 8b, when combined, constitute an explodedperspective view ofthe complete mandrel shown in FIG. 1. l

Referring to FIG. l, the mandrel designated generally as 11 is shown with a mill-roll of sheet material designated generally as l2 mounted'thereon. The mill-roll 12 -is indicated in dotted outline in FIG. l to present a better view of the mandrel 11.

The mandrel .11 comprises a anain shatt 13 which is oi suitable length and diameter to be mounted in a machine (not shown) to which a moving web of sheet material is `to be fed from the mill-roll 12.

The mill-roll 12 comprises a web or" sheet material 14 such as paper, plastic film, or metal foil for example, wound on a hollow cylindrical core l5 which may be formed vof aluminum tubing, cardboard tubing or the like.

Mounted on the main shaft 13 are two axially spaced supporting collars 16 and 117 The external diameter of the greater portion of collar 16 is slightly less than the internal diameter of the hollow core 15 for freely sliding engagement therewith. The supporting collar 16 is provided with an annular stop flange l@ which limits the longitudinal movement of the mill-roll y12 toward the left on the mandrel -11 and serves to locate the mill-roll 12 -in its correct longitudinal position on the mandrel 11 when the mill-roll 12 is in engagement with the flange '18. The collar 17 is similarly dimensioned to slide freely through the tubular mill-roll core i5. The collars 16 and 17 are adjustably tired to the main shaft 13 by set screws 19 and'2i, respectively, and may be positioned as desired on main shaft 13 in accordance with the width of the web 14.

The outer surface of the main shaft `131i has three centrally located longitudinal grooves 21 formed therein intermediate its ends. The grooves 21 are circumferentially spaced apart around the surface of the main sh i3. The number of grooves may be varied as desired, three grooves being illustratively shown in the embodiment of the invention herein described.Y

Disposed for pivotal movement in each of the three grooves 21 is a gripping ap member 23. Each gripping Hap 23 is rounded at its inner edge 24 but is other- Wise of generally rectangular cross-section. Each ap member 23 is provided at opposite ends with longitudinally extending pivot Shanks 25 and 26 of circular crosssection, the inner portion of the external surface of each of the pivot Shanks 25 and 26 forming a continuation of the rounded inner edge 24 of each gripping flap member 23. Each of the lgrooves 21 is bevelled at one'y side at 27 to permit free pivotal movement of the gripping .surely locked for ,grooves 21. The spring retaining collars 31 and 32 are -ing collar 31 has a Ywhich opens toward follow rotational movements 23, are therefore yieldingly urged by actuating dise A33 for is provi-ded with Vthree. l studs 29 of flap members 23 are sylidably disposed. The Vspring 41 thus urgesthe flap members 23 for Vrotation flap 23 mounted therein in aclekwise direction as viewed in FIG. 2, the opposite side of each groove 21 `cooperate with rotatable ap .actuating discs 33 and 34,

respectively.

The pivot Shanks 25 and 26 extend along'the grooves 2,1,and under-the inner circular surfaces of the spring retaining collars 31 and 3,2 and theaetuating discs 33 and 34, respectively, so that the ap members V23 are all sepivotal movement in their respective djustably fixed tothe main shaft 13 bytmeans of set screws 35 and 36, respectively, the spring retaining collars 31 and 32 being positioned to prevent ,longitudinal movement of ilap members 23 and actuating discs 33 and 34 Valong main shaft 13. One side of the spring .retaincircular groove 38 formed therein the actuating dise 33. The spring retaining collar 32 is similarly provided with. a Vcircular groove 39 which opens toward the actuating disc 33.

A helical compression'spring 40 is disposed in the groove 38-oftspring retaining collar 31 and a similar 'Spring 41 is disposed in the groove 39 0f ,Spring retaining collar 32. The spring 40 bears at oneV end against the upper side of a fixed stud 42 carried bythe spring `retaining collar 31 and disposed in the circular groove 38. rljhe opposite end of spring 40 bears against the uPPer fside of a movable stud 43xed to the rotatable actuating disc 33 for movement there 'th. The helical spring 40 is constrained by the side walls Vof the groove 38 to as- 'suine a generally semicircular configuration. Because of the accompanying friction against the side walls of the groove 38, it is desirable to use a spring which is not much longer than l180" of arc when disposed in the circular groove.

The actuating disc 33 is provided-with three lslots 44 in which the actuating studs 28 of flap members23 are radially movable and which constrain the studs 28 Ato of the disc 33. The flaps pivotal movement in a clockwise direction as viewed in 1 or in a counterclockwise direction as viewed in FIGS. 2, 8a and 8b, the disc 33 being continuously urged in such direction by the compression spring 40.

Similarly, at the right hand end of the mandrel 11 as viewed in FIGS. l, 3, 8a and 8b, one end of the cornpression spring Y41 disposed in the groove 39 o f spring retaining collar 32 hears against the upper surface of a fixed stud 45 in groove 39 and its opposite end bears against a movable stud 46 fined to rotatable actuating disc 34 for movement therewith. The actuating disc 34 slots 4 8 in which the actuating in unison with the spring 40, the action ofthe two springs 40 and 41 being cumulative and applied to opposite ends of each ap member 23 by means of the actuating discs 33 and 34 and the actuating studs 28 and 29, respectively.

The rotation of actuating disc 33 is .limited by a movable stop stud 49 carried by Athedisc 33 and which rnay move only between two circumferentially spaced fixed studs 50 disposed in the circular groove 38 of spring retaining collar 31. The rotation of actuating disc 33 is similarly limited by a movable Vstud 51 carried by disc 33 which is movable between spaced fixed stop studs 52 disposed in groove 39 of spring retaining collar 32.

In order to facilitate sliding the mandrel 111 into the core of a mill-roll, each of the `gripping ap members 23 is generally tapered'at its right hand end'as viewed in FIGS. l, 3 and 8a to provide a smooth cam surface 53 which will be engaged by the end of the mill-roll core 15. As the mandrel 111 enters the millfroll core 1.5, the

cere press simultaneously against the three cam Surfaces 53 and will cause the three flap members 23 to pivot in a clockwise direction as viewed in FIGS. 2, 8a and 8b, thereby rotating Vthe actuating discs 33 and 34 againstV the yielding pressure Vof compression springs 4t) and 41 and moving the ilap members 23 from their radially extended positions shown in FIG. 5 to the inclined retracted positions indicated in -FIG. 6.

The internal diameter of the mill-roll core l15 is such that a small clearance vis provided between the core 1S and the collars 16 and 17, this clearance being Imade as small as possible consistent with commercial variations in. the internal diameter 0f the cere 1S for various millrolls, :the .cle ance being auch as to provide a free Sliding tit. for the eellrs 15 and 16 the mandrel 11 is inserted in the core 15. Thus, the millfrell will be Supported by the collars 15 and 16 independently of Ythe gripping liap members 23.

In Opieitilltrit is assumed by way of illustration, that the web 14 is drawn under .tension applied by some web processing machine (not shown) to unwind the web A14 `from the millfroll 12. Under such circumstances, a fr- 'millfrolL however, the gripping ap members 23 are constrained to assume positions as indicated in FIG. 6, with their square outerfree edges or gripping edges 54 pressed yinto contact with the inner surface of the mill-roll core 15.

In FIG. y6, the web V14'is assumed to be undertension which causes the mill-.roll 12 to rotate in a ounterclockwise direction -as indicated by the arrowfthe mandrel l 11 is further assumedto be subjected to a control torque to oppose 'this rotation and regulate the web tension. As a result, square edges 54 of the gripping flap mem-bers 23 vare urged in a counterclockwise direction and the three square edges 54 are thereby simultaneously forced to dig more deeply into the inner surface of the mill-roll core 15 4for' transmitting the control torque in a positive and reliable manner from the mandrel -11 to the mill-roll 12. The mandrel 11 thus becomes locked to the mill-roll `12, without the manipulation of lany locking device, and is also centered coaxially with the main shaft 13.

If the direction of this torque is reversed, the flaps 23 will rotate in ya clockwise direction and disengage the square edges 54 Ifrom locking engagement with the core 15, except for friction caused by the relatively light pressure produced by the compression springs 40 and 41. This willreleasethe mandrel 11 so that it may be quickly and 'easily withdrawn an empty core.

The sharpness o f the square edges 54 may be varied andspecialhighfriction material or roughened gripping surfaces may 'be used to obtain the desired locking action.

in shown j.and described Without departing from Ythe scope of the invention as defined in theappended claims.

What's claimed is: Y 1. Afniandrel yfor supporting a roll of -web material Vwoundonl a tubular core, said mandrel comprising in combination: a main shaftV adapted Vto have-a control Vtorque applied thereto for regulating the tension in said web during the uuwinding 'of' said web from said roll; a

.5 plurality of gripping members carried by said shaft for rotation therewith, each of said gripping members being pivoted for movement about an axis parallel to the axis of said main shaft each of said gripping members comprising a vf-ree edge portion which moves outwardly from the laxis of said main shaft during said pivotal movement; resilient means yieldingly urging pivotal movement of said gripping members to move said free edge portions outwardly for engagement -with the internal surface of said core when said roll is mounted on said mandrel with a pressure which increases in accordance with increased tension in said web as said web is pulled from said roll against the action of said control torque, said pivotal axes being disposed with respect to the longitudinal axis of said main shaft to cause said pressure to increase sufciently to lock said roll to said mandrel; and a pair of collars iixed to said shaft and disposed in proximity to opposite ends of said gripping members, said collars each having a portion of external diameter slightly less than the internal diameter of said core for sliding freely through said core to permit insertion of said mandrel in said core and removal of said mandrel therefrom, said collars being arranged to support said roll on said mandrel independently of said gripping members.

2. A mandrel according to claim 1, in which one of said supporting collars comprises a stop flange for positioning said roll axially on said mandrel.

3. A mandrel according to claim 1, in which each of said gripping members is provided with a smooth cam surface located adjacent to the end of each gripping member which rst enters said core, sai-d cam surface being shaped to cause progressive pivotal movement of said gripping members `against the yielding action of said resilient means as said mandrel is inserted longitudinally into said core.

4. A mandrel for supporting a roll of web material wound upon a tubular core, said mandrel comprising, in combination: a main shaft adapted to have a control torque applied thereto for regulating the tension in said web during the unwinding of said web from said roll, said shaft having a plurality of longitudinal grooves formed therein; a plurality of gripping ilap members each disposed in one of said grooves for pivotal movement about an axis parallel to the longitudinal axis of said shaft, each of said gripping members comprising an elongated free edge gripping portion, said gripping portion being adapted to move inwardly and outwardly from the axis of said main shaft in the course of said pivotal movement; resilient means acting on said ap members and yieldingly urging pivotal movement of said ap members to move said gripping portions outwardly for engagement with the internal surface of said core when said roll is mounted on said mandrel, the direction of said control torque being such as to produce further pivotal movement of said ap members in the same direction as that urged by said resilient means during engagement between said gripping portions and said core accompanied by further outward movement of said gripping portions for locking said roll to said mandrel and core supporting means car ried by said shaft, said supporting means comprising a plurality of members adapted to t longitudinally slidably -Within said core and dimensioned to support said core independently of said flap members.

5. A web feeding device according to claim 4, in which said free edge gripping portions of said ap members are of substantially rectangular cross-sectional configuration, said locking action being obtained by the digging of one of the square edges of said rectangular conguration into the inner surface of said tubular core.

6. A web feeding device according to claim 5, in which each of said iiap members is provided with shank portions Which extend outwardly in said grooves beyond the ends of each flap member, said supporting means comprising collar means mounted on said main shaft and holding said shank portions in said grooves, said collar members being positioned to prevent longitudinal movement of said flap members.

7. A mandrel of the class described for rotatably supporting a roll of web material wound upon a tubular core, said mandrel comprising, in combination: a main shaft adapted to have a control torque applied thereto for regulating the tension in said web during the rotation of said roll; said shaft having a plurality of equally angularly spaced grooves formed in the surface thereof and extending parallel to the longitudinal axis of said shaft; a gripping flap member disposed in each groove for pivotal movement therein, each gripping flap member comprising a flap portion leaving a free gripping edge and two pivot shank portions extending along its associated groove beyond the ends of the iiap portion of said ap member; an actuating stud carried by each end of each gripping ap member and each disposed radially outwardly of one of said pivot shank portions; a pair of actuating discs rotatably disposed on said shaft adjacent the ends of said flap portions and encircling said shank portions to retain said flap members in said grooves and preventing longitudinal movement of said flap members, each of said actuating discs having a plurality of radially elongated slots formed therein, one of said actuating studs being disposed in each of said slots; and resilient means acting on each of said actuating discs to rotate each disc in the same direction and yieldingly urge pivotal movement of said iiap members to move the free gripping edges of said flaps outwardly with respect to the longitudinal axis of said main shaft for engagement with the internal surface of said core when said roll is mounted on said mandrel, the direction of `said control torque being such as to produce further pivotal movement of said ap members in the direction urged by said resilient means accompanied by further outward movement of said gripping edges for locking said roll to said mandrel.

8, A mandrel according to claim 7, further comprising a pair of spring retaining collars iixedly positioned on said shaft adjacent to said actuating discs, each of said collars having a circular groove formed therein; said resilient means comprising helical spring means disposed in each of said grooves.

References Cited in the flle of this patent UNiTED STATES PATENTS 1,188,369 Chernack June 20, 1916 2,416,785 Welch Mar. 4, 1947 2,474,672 Hill lune 28, 1949 2,576,254 Fletcher Nov. 27, 1951 FOREIGN PATENTS 386,435 Great Britain Ian. 19, 1933 

